[PATCH] [media] staging: allow omap4iss to be modular

[arnd@arndb.de (Arnd Bergmann)]

The OMAP4 camera support depends on I2C and VIDEO_V4L2, both
of which can be loadable modules. This causes build failures
if we want the camera driver to be built-in.

This can be solved by turning the option into "tristate",
which unfortunately causes another problem, because the
driver incorrectly calls a platform-internal interface
for omap4_ctrl_pad_readl/omap4_ctrl_pad_writel.
To work around that, we can export those symbols, but
that isn't really the correct solution, as we should not
have dependencies on platform code this way.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
This is one of just two patches we currently need to get
'make allmodconfig' to build again on ARM.

diff --git a/arch/arm/mach-omap2/control.c b/arch/arm/mach-omap2/control.c
index 751f354..05d2d98 100644
--- a/arch/arm/mach-omap2/control.c
+++ b/arch/arm/mach-omap2/control.c
@@ -190,11 +190,13 @@ u32 omap4_ctrl_pad_readl(u16 offset)
 {
 	return readl_relaxed(OMAP4_CTRL_PAD_REGADDR(offset));
 }
+EXPORT_SYMBOL_GPL(omap4_ctrl_pad_readl);
 
 void omap4_ctrl_pad_writel(u32 val, u16 offset)
 {
 	writel_relaxed(val, OMAP4_CTRL_PAD_REGADDR(offset));
 }
+EXPORT_SYMBOL_GPL(omap4_ctrl_pad_writel);
 
 #ifdef CONFIG_ARCH_OMAP3
 
diff --git a/drivers/staging/media/omap4iss/Kconfig b/drivers/staging/media/omap4iss/Kconfig
index 78b0fba..0c3e3c1 100644
--- a/drivers/staging/media/omap4iss/Kconfig
+++ b/drivers/staging/media/omap4iss/Kconfig
@@ -1,5 +1,5 @@
 config VIDEO_OMAP4
-	bool "OMAP 4 Camera support"
+	tristate "OMAP 4 Camera support"
 	depends on VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API && I2C && ARCH_OMAP4
 	select VIDEOBUF2_DMA_CONTIG
 	---help---